High pressure pump, frame and housing assembly

ABSTRACT

The invention is a high pressure pump, frame and housing assembly including a high pressure pump, electric motor, belt drive, metal frame, plastic housing and noise absorbing sheets that combine to suppress vibration, attenuate noise and allow viewing of the motorized pump assembly. The motorized pump produces a flow rate of at least 4 gpm at a pressure of at least 2,000 psi, while the assembly keeps the noise level at or below about 77 decibels. Vibrations are suppressed by the frame and housing which are formed by irregularly shaped and sized frame members, segments and panels. The housing panels combine with the porous noise attenuating sheets to form dead zones for absorbing noise. The sheets and dead zones are compactly arranged inside the frame segments. Two transparent panels form dual opposed windows for lighting and viewing the active internal components.

TECHNICAL FIELD OF THE INVENTION

This invention relates to a pump, frame, and housing assembly for a motorized, high pressure pump producing an output of at least 4 gpm and 2,000 psi of hydraulic pressure, where the assembly suppresses motor and pump vibrations, reduces noise to 77 decibels or less, and allows safe viewing of internal components during operation.

BACKGROUND OF THE INVENTION

Manufacturing systems and processes that require a source of high pressure fluid are well known. These systems increase manufacturing efficiency, reduce waist and improve the quality of goods. Many of these systems are computer controlled robotic systems that use a robotic arm to control and aim a high pressure stream of fluid. Washing, deburring and cutting systems are but a few examples of the many types of systems that require fluid pressures of 2,000 psi (pounds per square inch) or greater. Each year, the various uses and needs for these systems and processes continues to grow. These manufacturing systems incorporate high pressure pumps and relatively powerful motors that can pressurize a working fluid such as water to a desired hydraulic pressure at a flow rate needed to properly perform the system. Most manufacturing systems require a flow rate of at least 4 gpm (gallons per minute). An example of a conventional high pressure pump, electric motor and frame assembly is shown in FIGS. 1-4.

A problem with conventional high pressure pump and motor assemblies is excessive noise. High pressure pumps capable of producing the required pressures and volumetric flow rates needed for most manufacturing systems are noisy. The electric motor and pulley drive assembly only add to this noise level. In many conventional cases, the noise level of the motorized pump and frame assembly exceeds 90 decibels. Yet, prolonged exposure to this level of noise is known to cause hearing loss. This noise level can also lead to accidents because workers cannot hear each other talk, as human speech is typically about 75 decibels and is drowned out by the pumping unit. Workers may also be unable to hear other heavy equipment or vehicles in the area. Still, locating high pressure pumping units in remote parts of a plant or constructing a room for them is costly and often impractical.

Another problem with conventional high pressure pumps and motors is vibration. The high rates of speed and cyclical motion of the pump, motor and drive assembly generate vibrations that shake their supporting frame and the components attached to that frame. Industrial high pressure pumps typically take the form of positive displacement pumps. These pumps generate large pulses of energy and vibrations each time their piston or pistons are stroked to pressurize the working hydraulic fluid such as water. The pumps typically operate at several hundred rotations per minute (rpm). The electric motors typically used to drive the pumps rotate at even higher rates of speed. The various cyclical pulses and rotational vibrations of the motorized pump assembly can combine to harmonically excite the frame and produce even larger amplitude vibrations and shaking. These vibrations create excessive wear and tear on the equipment, can lead to malfunctions, and result in increased maintenance requirements for the equipment. These vibrations and shaking of components also increase the level of noise.

A still further problem with high pressure pumps and motors is visibility and lighting. The expensive, high speed equipment must be routinely inspected to ensure proper operation. Abnormalities that can lead to the rapid deterioration or degeneration of the equipment should be easily detected. For example, periodic visual checks for smoke, excessive shaking, or loosening or flaking of the drive belt, help indicate if service is required. Active components such as the motor, pump and drive assembly should be located where they are not visually obstructed by other components and are properly illuminated by light so that any abnormalities can be easily seen. Visibility and proper lighting are important because even trace amounts of smoke, belt ware or leaks can lead to rapid deterioration and even dangerous and costly disintegration of the high speed equipment. Yet, an acoustic housing that surrounds the active equipment tends to block visibility and lighting, and renders proper inspection and maintenance problematic.

A still further problem with high pressure pump and motor assemblies is ventilation. High pressure pumps and their motors need cooling. Using the air in the building to cool the equipment is common and economical. Higher horsepower electric motors typically include a fan to draw air into the housing to cool its internal components and prevent them from overheating. High pressure pumps also need air flow around them to prevent overheating. Enclosing a high pressure pump in a sealed housing can result in overheating, malfunction or reduced life of the pump or motor unless proper ventilation is provided. Yet, vent openings provide pathways for transmitting noise, and can render other noise attenuating methods ineffective.

A still further problem with high pressure pump and motor assemblies is safety. The shafts of the motor and pump spin at several hundred revolutions per minute (rpm). The drive belt and pulleys that join the drive and driven shafts of the motor and pump also turn at a high rate of speed. Any worker that inadvertently comes in contact with these components during operation can be severely injured. Although some designs include a cabinet that encloses the pulley and belt as in FIG. 3, this cabinet obstructs the view of these and other components during operation. The cabinet also requires workers to come close to the unit, open the cabinet, and even lean over the high speed components to inspect them during operation.

A further problem with motorized, high pressure pump assemblies is their bulky size. Although floor space in most manufacturing settings is at a premium, the components are typically arranged on a skid type frame having a large footprint as in FIG. 1. The pump, motor and pulley drive are mounted close to the floor to dampen vibrations and minimize their transmission to each other, as well as other static components such as the fluid storage tanks. Designs that rely on the dampening effect of the floor to reduce vibrations increase the footprint of the unit. The actively rotating components, as well as other relatively static components, are simply spread out over the length and width of the frame. This large footprint also increases the difficulty and cost of enclosing the components in a housing.

A still further problem with motorized high pressure pump assemblies is maintenance. For example, the oil level of the pump must be routinely checked and maintained. Yet, the frame sets on the floor and the active components are located near the floor. Workers must bend over or kneel down, open access doors or remove obstructions to inspect or perform routine maintenance on various components. Dirt and debris also collect under the unit which is at best difficult to clean, particularly during operation. This dirt and debris can be drawn into the motor or pump and cause damage, or be picked up by the drive belt and result in unnecessary injury or damage.

The present invention is intended to solve these and other problems.

BRIEF DESCRIPTION OF THE INVENTION

This invention relates to a high pressure pump, frame and housing assembly including a high pressure pump, electric motor, drive belt assembly, metal frame, plastic housing and noise absorbing sheets that combine to suppress vibration, reduce noise, and allow viewing of the motorized pump assembly. The motorized pump produces a flow rate of at least 4 gpm and hydraulic pressure of at least 2,000 psi, while keeping the noise level at or below about 77 decibels. Vibrations are suppressed by the frame and housing, which are formed by frame members, segments and panels having different sizes and shapes so that they do not vibrate at the same natural frequency, and tend to cancel or attenuate vibrations passing from one frame or panel member to another. Thin acoustic insulation sheets combine with the housing panels to form dead zones that absorb noise. The sheets and dead zones are compactly arranged inside the frame segments so that the size and footprint of the assembly is kept to a minimum. Two transparent housing panels form dual opposed windows that provide the lighting to and allow the viewing of the motorized pump assembly and other internal components.

One advantage of the present motorized pump assembly is its reduced noise level. Although the motorized high pressure pump produces hydraulic pressures of about 2,000 to 10,000 psi or more at flow rates of 4 to 18 gpm or more, the noise level of the assembly at a distance of three feet from the unit is kept to about 75 to 77 decibels or less. This noise reduction is a result of reduced vibration and the use and arrangement of noise absorbing sheets placed in the windows of the frame segments. The thin, plastic, sound absorbing sheets have a porous surface that dampens noise. The sheets are sonically welded to the inside surface of the plastic housing. The sheets are folded to form a box shape. The sheets have a flat main portion that is spaced from the housing to form a dead zone of air between the sheet and the housing. The sheets and dead zones are compactly arranged to fit within the windows of the frame segment. A bottom sheet is also located along the bottom of the frame. The motor intake air vent and the exhaust vent at the top of the frame include noise insulation and baffles. The dramatic reduction in noise of the present motorized pump assembly meets the noise level requirements for machinery and equipment used in many industrial setting such as Ford Motor Company manufacturing plants.

Another advantage of the present motorized pump assembly is vibration suppression. High pressure pumps generate large pulses of energy and vibrations. The drive motor also generates vibrations. The structure of the frame inhibits the transmission and multiplication or excitement of these vibrations. The frame is composed of upper and lower portions. The upper portion is formed by frame members with different cross sectional sizes than the lower portion. The frame is also formed by several frame segments. These segments have different shapes and sizes, and do not form a square. The platforms on which the motor and pump are mounted are also constructed differently and include plates having different thicknesses. This construction produces frame segments and parts with different natural frequencies that inhibit the multiplication or excitement of vibrations. The construction also helps attenuate and minimize the propagation of the motor and pump vibrations through the frame. The shafts of the motor and pump are also offset from the center of the housing, and flex hose and shock absorbing rubber mounting pads are used to reduce vibration excitement and propagation. This vibration suppression reduces the wear and tear on the frame, housing and internal components attached to the frame. The reduced vibration also reduces the noise level of the overall assembly.

A still further advantage of the present motorized pump assembly is the visibility and lighting of its active internal components. Good visibility and lighting are particularly important because external noise is below 77 decibels, while the background noise of many manufacturing settings is typically about or above 80 decibels. As a result, workers cannot hear component noises inside the acoustic frame and housing assembly that would otherwise signal a need for maintenance or an impending malfunction, such as a high pitched whir of a worn drive belt. Although the frame and housing assembly surround the internal components, two panels are transparent plastic to provide windows for viewing those components. The windows are located on the front and rear of the assembly. This opposed, dual window design allows light to enter the opposite side from the line of sight of the viewer to provide backlighting for each window. A worker can view the internal components through either window without shadowing that can hide or hinder the observation of smoke, leaks, belt deterioration or loosening, excessive vibration, or other sometimes difficult to detect abnormalities. The accumulation of belt flakes or leaking fluid at the bottom of the housing is easily seen through the front window, which spans from the bottom to the top of the assembly, and which is located directly in front of and provides unobstructed viewing of the pulley and drive belt assembly. The rear window is located directly behind and allows for unobstructed viewing of the pump and motor. The rear window is angled relative to the vertical front window. This angled arrangement inhibits the reverberation of noise between the windows, and provide a clear view of both the pump and motor, which are stacked one on top the other. The dual window design utilizes ambient room light and avoids the problems of providing and maintaining a fixed internal light source, which can also produce a shadowing effect. The ergonomic design also allows workers to properly inspect the internal components without bending over, kneeling down or contorting their body into an unnatural position. As a result, the expensive, high speed equipment can be routinely inspected to ensure their proper operation.

A still further advantage of the present motorized pump assembly is its ventilation. Both the pump and motor are adequately ventilated and cooled by room air so that they do not overheat. The high power electric motor and the pump are kept within design specifications during operation. The air vent openings in the housing include baffles to abate the transmission of noise, and are located where they do not obstruct visibility through the front and angled rear windows.

A still further advantage of the present motorized pump assembly is its added safety. The rotating shafts, pulleys and drive belt of the motorized pump assembly are enclosed in the frame and housing of the assembly. The windows are thick panels of transparent Lexan plastic. Workers do not have to open the housing or physically handle the unit to view the motorized pump assembly 15. Checking for smoke, excessive shaking, fluid leaks, belt flaking or loosening, bulging hoses, and other maintenance inspection requirements can be easily observed. Workers remain behind the housing and away from the spinning components.

A further advantage of the present motorized pump assembly is its compact size, which is achieved by a number of design features. First, the pump and motor have a stacked arrangement. The pump is located above the motor. Second, only active high speed components such as the pump, motor and pulley drive are enclosed in housing of the assembly. Static components such as tanks and control panels that do not require vibration and noise control are positioned outside the frame and housing. Third, the noise absorbing sheets are thin and effective. Bulky masses of insulation are not used. Fourth the noise absorbing sheets are located inside the openings or windows of the frame segments so that they do not increase in the overall size of the assembly. The surface area of the noise insulation actually exceeds the surface area of the interior space of the assembly. Thus, the overall assembly has a small footprint and conserves manufacturing floor space. The compact size also reduces the cost of enclosing the motorized pump in an acoustic housing.

A still further advantage of the present motorized pump assembly is its ergonomic design and ease of maintenance. By elevating the frame, workers can more easily perform routine maintenance such as oil changes, applying lubricants, filter cleaning or replacement, bolt tightening, hose replacement, etc. A small access opening is provided in the rear window so that a worker can check the oil level without removing any housing panels. The opening is located directly above the oil dip stick and allows the worker to see his or her hand and the dip stick as they reach into the housing. Workers do not need to bend over or work off the floor. The elevated design also allows dirt and debris to be easily cleaned away from the floor and around the unit, even during operation.

Other aspects and advantages of the invention will become apparent upon making reference to the specification, claims and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a conventional motorized pump assembly for a high pressure, positive displacement pump that provides discharge pressure of over 2,000 psi and has a noise level of over about 90 decibels.

FIG. 2 is a side view of the conventional motorized pump assembly of FIG. 1.

FIG. 3 is a rear view of the conventional motorized pump assembly of FIG. 1.

FIG. 4 is a top view of the conventional motorized pump assembly of FIG. 1.

FIG. 5 is a front perspective view of the present pump, frame and housing assembly with the front transparent panel and other exterior housing panels and insulation in place, and showing a partial view of the electric motor, high pressure pump and drive assembly.

FIG. 6 is a rear perspective view of the present pump, frame and housing assembly with the rear transparent panel and other exterior housing panels and insulation in place, and showing a partial view of the electric motor and high pressure pump.

FIG. 7 is an exploded, rear perspective view of the present pump, frame and housing assembly with the housing removed and to reveal the noise absorbing sheets, support frame, and motorized pump assembly.

FIG. 8 is a side view of the motorized pump assembly invention of FIG. 7.

FIG. 9 is a rear view of the motorized pump assembly invention of FIG. 7.

FIG. 10 is a top view of the motorized pump assembly invention of FIG. 7.

FIG. 11 is an exploded perspective view of the frame of the present motorized pump assembly showing individual noise attenuation sheets.

FIG. 12 is an overhead view showing noise level readings in decibels at various locations around the present motorized pump assembly during operation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

While this invention is susceptible of embodiment in many different forms, the drawings show and the specification describes in detail a preferred embodiment of the invention. It should be understood that the drawings and specification are to be considered an exemplification of the principles of the invention. They are not intended to limit the broad aspects of the invention to the embodiment illustrated.

The present invention pertains to a pump, frame and housing assembly generally indicated by reference number 10 and shown in FIGS. 5 and 6. The assembly 10 includes an internal motorized pump assembly 15 and a frame, housing and acoustic insulation assembly 50. The motorized pump assembly 15 includes an electric motor 20, a high pressure pump 30 and a drive assembly 40. The frame, housing and insulation assembly 50 includes a frame 60, housing 150 and acoustic insulation 200. The frame 50 supports the motorized pump assembly 15 and forms an interior space 55 sized to compactly contain these active components. The frame 60 also supports the housing 150 and insulation 200, which surround and acoustically insulate the active components and provide windows for viewing them.

The electric motor 20 has a housing 22 and rotating drive shaft 24. The motor 20 receives electric power via an electric cord 25 that is plugged into the main power supply system for the manufacturing plant. The motor 20 has an internal cooling fan that draws air through an intake tube 26 and into the housing 22 as shown in FIG. 7. The intake tube 26 is made of loaded rubber for acoustic purposes. A simple styrofoam baffle is also provided in the intake tube 26 for acoustic purposes. Air flows around the baffle and between the baffle and the vent tube. The electric motor 20 is preferably a three-phase, 25 horsepower (Hp) motor that rotates at about 1,200 to 1,800 rotations per minute (rpms). The motor 20 preferably has a foot mounted housing, weight of about 325 pounds, and length, width and height dimensions of about 500 millimeters (mm), 360 mm and 400 mm, respectively, such as the Model M3AA made by ABB of Detroit Mich. The air intake vent 26 is made of loaded rubber to help reduce noise transmission through its several openings in the housing 150.

The high pressure pump 30 is preferably a positive displacement pump designed to produce at least 2,000 pounds per square inch (psi) of hydraulic pressure. The pump 30 has an elongated housing 32 that extends horizontally as shown in FIGS. 7, 9 and 10. The pump housing 32 and its three internal pistons extend generally perpendicular to the motor housing 22. The pump 30 has an input or driven shaft 34 that is aligned generally parallel to the drive shaft 22 of the electric motor 20. The pump 30 has a low pressure inlet 35 and a high pressure outlet 36. The inlet 35 is connected to the low pressure or return line of the manufacturing system and carries fluid at a pressure of about 35 psi. The outlet 36 is connected to the high pressure line of the manufacturing system. The inlet and outlet 35 and 36 of the pump 30 are preferably connected to the piping of the manufacturing system via flex hose to help reduced vibration and noise. The pump 30 includes an oil level dip stick 37. In combination with the 25 Hp motor 20, the high pressure pump 30 is capable of producing a discharge flow rate of about 17 gallons per minute (gpm) at 2,000 psi, 9 gpm at 3,800 psi, 6 gpm at 6,000 psi, and 4 gpm at 9,000 psi. The high pressure positive displacement pump 30 has a weight of about 270 pounds, and length, width and height dimensions of about 760 mm, 400 mm and 260 mm, respectively, and is preferably of the type manufactured by Hammelmann Corp. of Dayton, Ohio as Model Number HDP 22 or 32. The pump 30 has a stroke length of about 60 mm and an average piston speed of 430, 510 or 610 rpms. Model Nos. HDP 20 and 40 are also believed possible for an alternate version of the assembly 10.

The pulley drive assembly 40 connects the electric motor 20 to the high pressure pump 30 as best shown in FIGS. 5, 7 and 8. This power transmission assembly 40 includes a drive pulley 42 that is rigidly secured to the drive shaft 24 of the electric motor 20, and a driven pulley 43 that is rigidly secured to the driven shaft 34 of the high pressure pump 30. A drive belt 45 is snuggly positioned around the pulleys 42 and 43 so that power from the motor shaft 24 is transmitted to the pump shaft 34. The drive pulley 42 has a smaller diameter than the driven pulley 43 so that the pump shaft 34 rotates at a slower speed than the motor shaft 24. The circumference of the driven pulley 43 is about 4.3 times greater than the circumference of the drive pulley 42. As discussed below, the height of the electric motor 20 is adjustable to maintain the belt 45 in tight engagement with the pulleys 42 and 43. Although the pulley drive 40 is shown and described, those of skill in the art should understand that other drive mechanisms could be used without departing from the broad aspects of the invention. Similarly, although an electric motor 20 and positive displacement pump 30 have been shown and described, those of skill in the art should understand that other types of motors and pumps could be used without departing from the broad aspects of the invention.

The frame, housing and insulation assembly 50 form an enclosed volume or space 55 for housing the motorized pump assembly 15 as shown in FIGS. 5 and 6. The motor 20 and pump 30 are offset a slight distance from the centerline 57 of the assembly 50 as best shown in FIG. 9. This assembly 50 includes a frame 60, housing 150, and a plurality of noise absorbing sheets 200. The frame 60 has a front 61, rear 62, top 64, bottom 65, and sides 66 and 68 as shown in FIGS. 7-10. The frame 60 is robustly designed to support the motorized pump assembly 15, as well as the housing 150. The pulley drive 40 is located adjacent the front 61 of the frame 60, and the elongated pump 30 extends toward the left side 68 of the frame. The frame 60 is formed by a plurality of frame segments 70. These segments 70 include a front segment 71, lower and angled upper rear segments 72 and 73, a top segment 74, a bottom segment 75, lower and upper right side segments 76 and 77, lower and upper left side segments 78 and 79, and an arcuate side frame segments 80. Other than arcuate segment 80, each segment 70 has four sides. Each segment 70 is welded or otherwise rigidly joined to its adjacent segments to form an irregularly shaped box-like enclosure.

Each segment 70 has at least two sides of unequal length for vibration suppression and noise reduction reasons. No segment 71-80 has a square or equilateral triangular configuration. The front, rear, top, and bottom segments 71-75 each have a rectangular shape that is different from any other segment 70. Although the lower side segments 76 and 78 share a common rectangular shape, this rectangular shape differs from the other segment 70. Similarly, the upper side segments 77 and 79 have a trapezoidal shape that differs from the other segments 70, and the arcuate side segment 80 have a curved shape that differs from the other segment.

The segments 70 are formed by individual frame members 91 that are welded or otherwise integrally connected. Adjacent segments 70 share a common frame member 91. Segments 71-79 are each formed by four elongated, perimeterally aligned, frame members 91. The front, side and rear segments 71-73 and 76-79 each include a top, bottom and side members 91. Similarly, the top and bottom segments 74 and 75 each include a front, rear and two side members 91. The bottom, lower rear and side segments 72, 75, 76 and 78 are formed by the lower frame members 92. The lower members 92 have a tubular construction with a cross-sectional shape of 1½ inches by 3 inches. The top, upper rear and side segments 73, 74, 77 and 79 are formed by upper frame members 94. The upper members 94 have a tubular construction with a cross-sectional shape of 1½ inches by 1½ inches. Because the front frame segment 71 spans from the top 64 to the bottom 65 of the frame 60, it includes both upper and lower frame members 92 and 94. The arcuate segment 80 is formed by two arcuate frame members 96 to help enclose the outer end of the high pressure pump 30. Arcuate segments 96 are spaced apart and in aligned registry with each other, and extend from the left side 68 of the fame 60. Except for the bottom segment 75, each segment 70 is free of any cross bracing between its respective members 91. As a result, the entire inner side wall 98 of each of these segments 70 forms an opening or window 100 that is free of any obstructions.

The lower segments 73, 75, 76 and 78 and their respective lower frame members 92 form a lower portion 110 of the frame 60. This lower portion 110 defines a lower interior space 112 of the entire enclosed area 55. The upper frame segments 72, 74, 77 and 79 and their respective upper frame members 94 combine to form an upper portion 115 of the frame 60. This upper portion 115 defines an upper interior space 117 of the entire interior 55. The frame 50 is elevated from a supporting surface by a set of four legs 119. Each leg 119 extends downwardly from one of the four corners of the bottom frame segment 75. Each leg includes an adjustment shoe for leveling the frame. The bottom segment 75 includes a set of two forklift tubes 142 for picking up and moving the assembly 10.

A lower platform 120 supports the electric motor 20. This platform 120 includes a set of cross beams or tubes 122 that are welded to and extend between the side frame members 92 of the bottom frame segment 75. A lower mounting plate 123 is welded or otherwise rigidly secured to these cross beams 122. A set of four adjustable mounting legs 124 support a generally horizontal, upper mounting plate 125. The mounting plate 125 has a thickness of about ½ inch. The motor 20 is bolted to this plate 125. The adjustable legs 124 are used to maintain the desired tension of the belt 45, and keep the belt in secure friction bearing engagement with pulleys 42 and 43.

An upper platform 130 supports the high pressure pump 30. The upper platform includes a set of cross beams or tubes 132 extending between the upper side frame members 92 of the lower side frame segments 76 and 78. Tubular mounting posts 134 are welded to these cross beams 132 to elevate an upper plate 135. The mounting plate 135 has a thickness of about one inch. The pump 30 is bolted to this plate 135. The size, shape and thickness of the mounting plates 125 and 135 are different to help suppress vibration and minimize noise. The mounting posts 134 elevate the pump 30 to a location that is cantered from but more near the center of the upper interior space 117 of the frame 50. Both the motor 20 and the pump 30 are slightly cantered from the center of the interior area 55 towards the right side 66 of the frame 50 to further assist in suppressing vibration and attenuating noise.

The housing 150 surrounds and encloses the motorized pump assembly 15 interior space 55 and frame 60. The housing 150 is formed by a front panel 151, upper angled and lower rear panels 152 and 153, top panel 154, side panels 156-159, and arcuate panels 160 and its side panels 161. The panels 150 are robustly designed to protect the motorized pump assembly 15 from being inadvertently struck by an external object, and protect workers from any parts such as the drive belt 145 that may become detached during operation. The housing 150 has a height of about 4⅓ feet without its legs 119 and just 5⅓ feet with its legs. The housing has a width of 2½ feet without the arcuate portion, a width of about 3½ feet with the arcuate portion, and depth of about 3½ feet.

The front panel 151 and upper angled rear panel 152 are transparent. Each of these panels 151 and 152 is intended to form a window allowing ambient room light to enter its internal space 55 and for viewing the motorized pump assembly 15 and interior space. These dual opposed windows 151 and 152 are preferably made of Lexan plastic and have a thickness of about ¼ inches. The front panel or window 151 provides an unobstructed view of the drive assembly 40, as well as a view of the motor 20 and pump 30 themselves located behind the drive assembly. The rear angled panel or window 152 provides an unobstructed view of both the motor 20 and pump 30. The rear angled window 152 includes an access cap 175 sized to allow a worker to insert his or her hand to remove and check the oil level dip stick 37 of the pump 30. Any undesired smoke, excessive shaking of the motor 20 or pump 30, loosening or flaking of the drive belt 45, leaking of pressurized fluid, or other observable signs indicating a need for maintenance, can easily be seen through these windows.

The remaining panels 153-161 are opaque, and are not intended to help acoustically insulate the assembly 10. The lower rear 153, top 154, side 156-159, and arcuate 160 and 161 panels are made of high density polyethylene (HDPE) plastic or marine plastic of the type used in the boat industry. Each panel 153-161 is approximately ½ inches thick. The bottom panel 155 is a metal plate 155. The perimeter of each panel 151-161 is bolted or otherwise securely fastened to its respective frame segment or segments 70. The panels 151-161 substantially completely enclose the interior area 55 of the assembly 10. The vents 153 a and 154 a and bottom plate 155 allow some open, baffled or acoustically insulated pathways between the interior 55 and the exterior of the assembly 10. Baffle 28 is placed over vent 153 a, spaced from and attached to the housing panel 153. The outlet vent 154 a in top panel 154 allows air to flow past the pump 30 and out of the interior area 55 so that the heat generated by the motor 20 and pump 30 is expelled. Each of the panels 151-161 is shaped so that its outer perimeter flushly engages the outer edge of its respective frame segment 70. Each panel 151-161 has an inside surface facing the interior area 55. Although the perimeter of each panel 151-161 abuts its frame segment 70, a main inner portion of the inside surface 171 of each panel remains free of obstructions, except for side panel 158 which has an opening cut into it for receiving the outer end of the pump 30.

Acoustic or noise-absorbing sheets 200 are placed in the windows 100 of the frame segments 70 covered by opaque housing panels 153-160. These sheets 200 are high density polyethylene (HDPE) plastic that are machined to have a roughened and micro-perforated surface 201. Although the pores go completely through the sheet 200, from one side of the sheet to the other, they are very small and do not readily permit air flow through the sheet. The acoustic sheets 200 have a thickness of about 0.04 inches, a density of about 0.95 grams per cubic centimeter (g/cc) and are preferably of the type manufactured by American Acoustical Products of Holiston, Mass. under the brand name Millennium Material (MM).

The acoustical sheets 200 are self-supporting and are preferably formed into a box-like structure 204 for additional rigidity. The box structure 204 has a flat inwardly facing main portion 205, two opposed spacing legs or flanges 206, and a flat rearwardly facing portion 207. The rear portion 207 is sonically welded to the inside surface 171 of its respective housing panel 153-160. The main inwardly facing portion 205 is spaced from its rear portion 207 and the surface 171 of its respective panel 153-160 a distance of about 1 to 4 inches and preferably about 2 inches. The panels 153-160 can include spacing bars projecting from their surface of 171 to help maintain the spacing of the main portion 205 of each sheet 200 and its box-like structure 204. Each acoustic sheet 200 or box shaped structure 204 is shaped to flushly fit between the side walls 98 of its respective frame window 100. The box shaped 204 acoustic sheet 200 inserted into the window 100 of the top segment 74 has slits 209 that form a baffle and cooperate with the vent 154 a in the upper panel 154. The frame and housing assembly 50 preferably includes eight acoustic sheets 213-220, one for each acoustically insulated segment 73-80.

Noise absorbing pockets or dead zones 240 are created by spacing the main portions 205 of the acoustic sheets 200 from its rear portion 207 or the surface 171 of its respective housing panel 153-160. These dead zones 240 combine with the acoustic properties of the sheets 200 to reduce or attenuate any noise trying to pass through the frame, housing and insulation assembly 50. The dead zones 240, and the acoustic sheets 200 and their U-shaped or box-like structures 204 are located between the sidewalls 98 of the frame members 91 forming the windows 100 of the frame segments 70.

The following formula is widely accepted to calculate noise reduction:

IL=TLc+10 log(({grave over (α)}Sa+0.05(St−Sa))/St)

Where:

-   -   IL=maximum achievable reduction in dB     -   TLc=composite transmission loss     -   {grave over (α)}=sabine absolution coefficient     -   Sa=total area of sound absorption     -   St=total surface area of enclosure

In the present design, the total surface area of the interior space 55 and the surface area of the noise absorbing materials such as loaded rubber vent 26 and sheets 200 are as follows:

Exterior Area Acoustic Area Front window 71 10.59 Front 0.0 Angled window 72 7.29 Angled 0.0 Back segment 73 5.38 Back 213 8.2 Top segment 74 2.69 Top 214 4.4 Bottom segment 75 7.68 Bottom or base 215 10.4 Side segments 76, 77 11.95 Upper left side 217 6.9 Side segments 78, 79 11.95 Lower left side 216 8.1 St = 57.53 Upper right side 219 6.9 Lower right side 218 8.1 Internal to cap 214 11.4 Sa = 64.4

For a motorized pump assembly 15 having an output of 90 decibels and the following composite transmission loss (TLc) and sabine absolution coefficient ({grave over (α)}), we obtain the following theoretical achievable reduction (IL) and projected decibel levels. These projected decibel levels coincide with the actual decibel levels obtained for the pump, frame and housing assembly 10 as shown in FIG. 12.

Frequency (Hz) TLc A IL Decibel level 100 7.4 0.5 13.1 76.9 500 10.9 0.6 17.7 72.3 1,000 16.7 0.85 27.1 62.9 10,000 11.3 0.7 20.7 69.3

The acoustic frame, housing and insulation assembly 50 preferably does not contain opposed parallel surfaces that are not acoustically insulated and would reflect noise back and forth in an excited reverberating manner. Although transparent panels 151 and 152 are not acoustically insulated, they are also not parallel so that sound waves do not reverberate back and forth between them. At least one of each pair of opposed parallel panels 151 and 153, 154 and 155, 156 and 158, and 157 and 159 has acoustic insulation to reduce noise. The side panels 161 of the arcuate portion 160 are also preferably not parallel.

Acoustic measurements taken for the motorized pump assembly 15 mounted on a frame without the housing 150 and acoustic insulation 200 produce noise levels of about 90 decibels or more at a distance of three feet from the equipment 15. With the motorized pump assembly 15 mounted to the frame and housing assembly 50 with housing 150 and acoustic insulation in place, the assembly 10 produces acoustic measurements of about 75 to 77 decibels taken at locations of about three feet from the equipment 15 as shown in FIG. 12.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the broader aspects of the invention. 

1. A high pressure pump, frame and housing assembly with vibration suppressing, noise attenuating and internal viewing features, said high pressure pump, frame and housing assembly comprising: a frame having front, rear, top, bottom and side segments that define an interior space and lower and upper portions, said lower portion having a lower platform and said upper portion having an upper platform, each of said segments being formed by several elongated, perimeterally aligned, frame members to define a frame segment opening, at least two of said frame members of each of said segments have a different length, and said lower portion being formed by lower frame members having a first cross-sectional shape and said upper portion being formed by upper frame members having a second cross-sectional shape, said first cross-sectional shape being smaller than said second cross-sectional shape; a motorized pump assembly including a motor, a high pressure pump, and a drive assembly, said motor having a drive shaft and being adapted to produce at least 7.5 Hp, said motor being mounted to said lower platform, said pump having a driven shaft, an inlet port and an outlet port, and being adapted to produce a flow rate of at least 4 gpm and a discharge pressure of at least 2,000 psi, said pump being mounted to said upper platform, and said drive assembly including rotatable drive and driven members, said drive member being fixed to said shaft of said motor, and said driven member being fixed to said shaft of said pump, said drive member rotatably driving said driven member; a housing secured around said frame to enclose said interior space and said motorized pump assembly, said housing being formed by a plurality of individual panels, each panel enclosing at least one frame segment, at least two of said panels being transparent to form dual opposed windows, one of said windows being at an angle relative to said other window, each of said windows allowing ambient light into said interior space to provide backlighting for said other window, and said windows allowing viewing of said motor, pump and drive assembly from locations exterior to said housing during operation of said motorized pump assembly; a plurality of noise attenuating sheets located in said frame segment openings, said sheets being shaped for substantially flush engagement with said frame members forming its said frame segment opening, said sheets having a main portion spaced a distance of at least about one to four inches from its said panel for its said segment to define a dead zone, said dead zone containing ambient air between its said attenuating sheet and said housing; and, wherein said motorized pump assembly has a noise level of below about 77 decibels during operation when measured at location exterior to said pump, frame and housing assembly.
 2. The high pressure pump, frame and housing assembly of claim 1, and wherein said noise attenuating sheets are thin plastic sheets that are micro perforated to absorb noise.
 3. The high pressure pump, frame and housing assembly of claim 2, and wherein said noise attenuating sheets have opposed legs that space its said main portion from said its said panel.
 4. The high pressure pump, frame and housing assembly of claim 3, and wherein said noise insulation has a combined surface area (Sa) greater than the combined surface area of the interior space of said assembly (St).
 5. The high pressure pump, frame and housing assembly of claim 1, and wherein said housing substantially completely encloses said interior space.
 6. The high pressure pump, frame and housing assembly of claim 5, and wherein said one of said dual opposed windows is a vertical front window that spans from said bottom to said top of said frame, and said other window is a rear window that is angled relative to said front window.
 7. The high pressure pump, frame and housing assembly of claim 1, and wherein said pump produces a discharge pressure of between 3,000 and 5,000 psi.
 8. The high pressure pump, frame and housing assembly of claim 7, and wherein said motor is adapted to produce between about 7.5 to 25 Hp, and said pump and motor produce a flow rate of between about 4 to 18 gpm.
 9. The high pressure pump, frame and housing assembly of claim 8, and wherein said motor is an electric motor and said pump is positive displacement pump.
 10. The high pressure pump, frame and housing assembly of claim 1, and wherein said drive assembly is a pulley and drive belt assembly drive and driven pulleys, and said drive pulley has a smaller diameter than said driven pulley.
 11. The high pressure pump, frame and housing assembly of claim 1, and wherein said frame has an ergonomic design that includes legs to elevate said pump and motor from a supporting surface.
 12. The high pressure pump, frame and housing assembly of claim 1, and wherein said frame includes a centerline, said lower platform includes a lower plate with a first thickness for securing said motor, and said upper platform includes an upper plate with a second larger thickness for securing said pump, said pump and motor being offset from said centerline.
 13. The high pressure pump, frame and housing assembly of claim 1, and wherein said inlet and outlet of said pump each include a flex hose, and wherein said motor and pump are mounted on vibration absorbing pads.
 14. A frame and housing assembly with vibration suppressing, noise attenuating and internal viewing features for a motorized pump assembly including a motor, a high pressure pump and a pulley drive assembly, the motor being adapted to produce at least 7.5 Hp, the pump having inlet and outlet ports and being adapted to produce a flow rate of at least 4 gpm and a discharge pressure of at least 2,000 psi, and the pulley drive assembly including a drive belt and rotatable drive and driven pulleys, the drive pulley being fixed to a shaft of the motor, and the driven pulley being fixed to a shaft of the pump, and said frame and housing comprising: a frame having front, rear, top, bottom and side segments that define an interior space and lower and upper portions, said lower portion having a lower platform, and the motor being mounted to said lower platform, and said upper portion having an upper platform, and the pump being mounted to said upper platform, each of said segments being formed by several elongated, perimeterally aligned, frame members to define a frame segment opening, at least two of said frame members of each of said segments have a different length, and said lower portion being formed by lower frame members having a first cross-sectional shape and said upper portion being formed by upper frame members having a second cross-sectional shape, said first cross-sectional shape being smaller than said second cross-sectional shape; a housing secured around said frame to enclose said interior space and the motorized pump assembly, said housing being formed by a plurality of individual panels, each panel enclosing at least one frame segment, at least two of said panels being transparent to form dual opposed windows, one of said windows being at an angle relative to said other window, each of said windows allowing ambient light into said interior space to provide backlighting for said other window, and said windows allowing viewing of the motor, pump and pulley drive assembly from locations exterior to said frame and housing assembly during operation of the motorized pump assembly; a plurality of noise attenuating sheets located in said frame segment openings, said sheets being shaped for substantially flush engagement with said frame members forming its said frame segment opening, said sheets having a main portion spaced a distance of at least about one to four inches from its said panel for its said segment to define a dead zone, said dead zone containing ambient air between its said attenuating sheet and said housing; and, wherein the motorized pump assembly has a noise level of below about 77 decibels during operation when measured at a location exterior to said frame and housing assembly.
 15. The frame and housing assembly of claim 14 and wherein said noise attenuating sheets are thin plastic sheets that are micro perforated to absorb noise.
 16. The frame and housing assembly of claim 14, and wherein said housing substantially completely encloses said interior space.
 17. The frame and housing assembly of claim 16, and wherein said one of said dual opposed windows is a vertical front window that spans from said bottom to said top of said frame, and said other window is a rear window that is angled relative to said front window.
 18. The frame and housing assembly of claim 14, and wherein the motor is an electric motor adapted to produce between about 7.5 to 25 Hp, the pump is a positive displacement pump adapted to produce a flow rate of between about 4 to 18 gpm and a discharge pressure of between about 3,000 and 5,000 psi. 